The objective of the overall research in this laboratory is centered on achieving as complete a description as possible for the structures of peptides, proteins, nucleic acids and their complexes in solution, principally by NMR spectroscopy. At present particular emphasis is being placed on developing approaches which allow the investigation of larger systems as well as increase the precision with which these solution structures can be obtained. Structures for several proteins have been determined and analyzed. These include the Zinc-finger domain of a human enhancer binding protein, human thioredoxin, and the cytokine interleukin-8. These solution structures represent high resolution structures, with rmsd values of approximately 0.4 angstroms for the backbone and 0.6-0.9 angstroms for all atoms. In addition to structural studies, novel NMR technology allows the detailed study of protein dynamics and a detailed investigation has been carried out for the protein interleukin-lo. Using two-dimensional inverse detected hetronuclear N-15/H-l NMR spectroscopy, N-15 spin-lattice and spin-spin relaxation times and NOE data were collected and analyzed, demonstrating motions on three different time scales for the backbone amide groups. Work is in progress on several other proteins, such as the DNA binding protein ner from phage Mu, several interleukins , the RNase-H domain of HIV-1 reverse transcriptase and Ascaris trypsin